Those biological studies which seek to probe the secrets of nature have also recognized love as the key of life. Scientists have at last perceived, after much research, this most evident fact: that it is love which preserves the animal species, and not the "struggle for existence." In fact, the struggle for existence tends to destroy; and as regards survival, this is not the exclusive privilege of the "fittest," as was at first supposed. But existence is indeed bound up with love. Indeed, the individuals who struggle and conquer are adults; but who is it that protects the new-born creature and infant life in process of formation? If a hard and horny covering is the natural protection of his species, he does not possess it; if it is strength of muscle, he is weak; if it is tusks, he is without them; if it is agility, he cannot yet move; if it is fecundity, he is not yet mature. Therefore, all species should have become extinct, for there is none so strong but that he once was weak; and there is no infancy which is not more feeble than any adult life. It is love which protects all this weakness, and explains "survival." Maternal love, indeed, is studied to-day with the deepest attention by our scientists as a natural phenomenon. If the struggle for existence presented to us a uniform picture of destruction, the phenomena of maternal love are to-day revealed to us in the richest and most fascinating forms, which almost represent the occult and sentimental aspect of the marvelous varieties of forms in nature. It is seen at last to be one of the "fundamental characteristics of the species," which should be recognized by all students.